Mode of manufacturing air-chambers for relief-valves.



V H. BURNET. MODE OF MANUFACTURING AIR CHAMBERS FOR RELIEF VALVES.

APPLICATION FILED JULY 7, 1908.

Patented Sept. 29, 1908..

WITNESSES.

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HUGH BURNET, or OTTAWA, ONTARIO, CANADA.

MODE OF MANUFACTURING AIR- CHAMBERS FOR RELIEF- VALVES.

Specification of Letters Patent. I

Patented Sept. 29, 1908.

Application filed July 7, 1908. Serial No. 442,427.

To all whom it may concern:

Be it known that I, HUGH BURNET,'Of the city of Ottawa, in' the county of Carleton, Province of Ontario, Canada, have invented certain new and useful Improvements in Modes of Manufacturing Air-Chambers for Relief-Valves, of which the following is a specification. 1

My invention relates to an improved method of manufacturing air chambers for relief valves, and particularly to the method of filling the air chamber, whereby it will be extremely sensitive to changes in temperature and will operate effectually and satisfactorily.

In using air relief valves for radiators, it is practically necessary. that the valve should automatically open when the temperature of the room falls below about sixty degrees temperature and thus permit the cold air which has formed in the coils or radiators durin the process of condensation to esca e and a 0 enable the. water to drain off to t e boiler. i

The actuation of the valve proper to which this invention refers is controlled by an expansible air chamber having distensible ends, and in experimenting I have found that it is necessary, if the valve is to open at the proper moment, that the chamberbe sealed while the chamber itself and the air thereinis at a temperature slightly too cold for comfort,

. for instance, at about 60 F. The air inside the chamber will thus be of a certain density and as long as the temperature of the room in which the valve is used remains above F. the ends of the chamber will be distended sufliciently by the expansion of the air to maintain the valve closed, but as soon as the temperature falls below that amount it will 0 en and permit the air to escape from and t e steam to flow into the radiator.

According to the present invention during filling of the chamber, communication is established between the interior of the chamber and the surrounding atmosphere while the chamber is immersed, in a temperaturechanging medium, said medium being of'a predetermined temperature below that desired in the room in which the valve is designed to operate, the sealing of the chamber being effected when the .air therein has reached said predetermined temperature, all

as hereinafter more fully set forth and described in the accompanying specification 5 and drawings.

In the drawings,,.-Figure 1 is a vertical sec-- air through the casing.

tion through a valve according to the present invention, showing the air chamber distended. Fig. 2 is the same view with the valve open. Fig. 3 is a top view. Fig. 4 is a pers )ective view of the retaining memberfor t e ball valve. Fig. 5 is a sectional View through a vessel containing the cooling medium, in'

ports a short externally screw-threaded top' 12 adapted to be connected to the heating system. The bottom 13 of the casing is slightly concave, being thereby'adapted to fit into the slightly concaved end of the expansion chamber when the valve is open, as shown in Fig. 2, whereby there-will be no lost motion 1n the operation of the valve.

B represents the inner air chamber formed of a stiff cylindrical side portion 14 and flexible disks 15 and 16 forming the ends of the-chamber, which are adapted to be distended outwardly by the expansion of the air contained therein. Actuated by the distention of the uppermost disk 15 is the ball valve C supported by means of a retaining member I) which is formed with a plurality of spider arms 17 extending over the top of the disk 15 and a plurality of upstanding arms 18 bearing against the side of the ball. The ball is adapted to seat against a flange 19 formed around an aperture in a disk 20, which rests on a small flange 21 formed on the to 3 of the casing and held thereon by the cap which has at the side an internally screw-threaded flange 22 which engages a corresponding screw-threaded portion on the outside of the casing, the capitself being dome-shaped and having perforations 23 therein for the escape of air. It will thus be seen that under ordinary conditions the air can flow freely through the valve and escape. As soon, however, as any steam attempts to pass, the air within the chamber B will expand and distend the ends as shown inFig. 1, and seat the valve D, which will prevent passage of The power to operate the valve is obtalned in reality from the difference in pressure between the heated air in the inside chamber and the pressure of the steam surrounding the same, this difference being caused by the constant radiation going onin the outside casing, which keeps the air in the cylinder hotter than the surrounding film of steam. In addition to this, the valve would be seated b any water flowing into the easing, as in t s case, the air chamber would act as a float to raise and seat the ball 0.

As hereinbefore explained, it is necessary to seal the air chamber B while the chamber itself and the air. therein is at a determined temperature somewhat lower than the desired temperature of the room, and it is important to note that in using the valves the altitude of the place would have to be taken into account, as a chamber sealed at sea level would be not quite so efiicient at one thousand feet above sea level. To effect this sealing at the correct temperature, a small aperture 24 is first punched in the side of the air chamber B and then the end disks 15 and 16 are soldered in position. The chamber is then immersed in a cooling liquid,

such as water, in a vessel F, which has its temperature the same as that temperature at which it is desired to have the air in the chamber B, the small aperture 24 being alone exposed above the surface of the water. The chamber will thus rapidly fill with air at the temperature of'the liquid and while it is still in said li uid, the small aperture 24 is sealed with so der or other sealing means to prevent escape of the air.

When this above described process is completed, the air in the chamber will be sealed up having a certain density and when the c amber is at the temperature at which the 'chamber'was' sealed, the end disks will be level or slightly concave but when the temperature is raised above that they will be convexed which will maintain the valve closed until the temperature of the room dro s below that at which the chamber was sea ed, when it will at once open.

As many changes could be made in the above construction, and many apparently widely different embodiments of my invening the air in said chamber to a predetermined temperature below that of the normal temperature of the room, the temperature of which is to be governed, wlnlc said chamber is open to the atmosphere and then sealing said chamber.

2. The mode of filling the air chambers of automatic radiator valves which consists in establishing communication between the interior of said chamber and the surrounding atmosphere until the air within said ehamber reaches a certain predetermined temperature below the desired temperature of the room in which the valve is designed to operate, and then sealing said chamber.

3. The mode of filling the air chambers of automatic radiator valves which consists in establishing communication between the in terior of said chamber and the surrounding atmosphere immersing said chamber in a temperature changing medium, said me dium being of a predetermined temperature below that desired of the room in which the valve is designed to operate, and finally sealing said chamber when the air therein has reached said predetermined temperature.

In witness whereof I have hereunto set my hand 1n the presence of two witnesses.

HUGH BURNE'I.

Witnesses:

RUssnL S. SMART, WM. A. WYMAN. 

